Snap Setter

A snap fastener is made of four small metal pieces — a cap and socket on one side, a stud and post on the other — and a snap setter is the pair of struck tools that presses each half together over a punched hole in the leather, crimping the post so the assembly can't pull apart. Like a rivet setter, it works in tandem with a flat or shaped anvil that supports the piece from underneath while the setter directs the hammer blow into the top.

Because a full snap needs two separate assemblies set on two different pieces of leather (or two spots on the same piece, for an overlap closure), the process is essentially the rivet-setting process done twice, once for the cap/socket half and once for the stud/post half.

How to use it

Punch a hole slightly smaller than the snap post's diameter at each snap location.
For the socket half: place the socket piece post-up on the anvil, slide the leather's hole over the post, then fit the cap over the top, sandwiching the leather between the two.
Position the setter over the assembly and strike firmly and evenly with a mallet until the socket locks onto the post.
Repeat the process for the stud half on the second piece of leather, using the matching setter and anvil combination for that half.
Test that the two halves snap together smoothly and don't feel loose or overly stiff.

💡 Tip

Use a mallet or rubber hammer rather than a steel one, and strike with moderate, controlled force — hitting too hard is a common way to bend or deform the cap, which is difficult to fix once it happens.

Care

Keep the setter and anvil faces clean and free of dents, since any distortion in the tool transfers directly to every snap set afterward. Store the pieces together so the matched setter and anvil for each snap size don't get mixed up with sets for a different size or brand.

How to use it

Care

Sources